A router is a device that forwards data packets between computer networks, creating an overlay internetwork. A data packet is forwarded from one router to another through the networks that constitute the internetwork until it gets to its destination node. Routers on the internet may control traffic. The act of dropping packets to “slow” down flows is called shaping and policing.
Most modern routers use queues to segregate traffic. The router may use upon the queue a number of Advanced Queue Management (“AQM”) techniques. One of the existing AQM techniques to control traffic is called a drop tail technique. This technique involves dropping all incoming packets when a queue becomes full. When the packets exit the queue and the queue size lowers, then incoming packets are admitted. Another one of the AQM techniques is called a Random Early Detection (“RED”) technique. According to the RED technique, a queue threshold is set at two levels. When the queue reaches the first threshold, the packets are randomly dropped. Once the queue reaches the second threshold then all incoming packets are dropped, as in the drop tail technique.
For the above-mentioned AQM techniques, the routers have no knowledge or awareness of the traffic that they are dropping. For non-congestion controlled flows, such as streaming video, as the number of users increases, all packets start dropping. This typically results in a poor video (e.g., choppy frames, or video freezing) for every user. Ultimately this can lead to a situation when none of the users see video. As a number of users increases, the existing techniques may not maintain a quality data traffic throughput.